In wireless communication the operating frequency bands are selected on the demanded and available bandwidths. System concepts like LTE and LTE-A introduce in particular the capability of high data rate wireless communication. To achieve the high data rate and high performance operation, large Bandwidths are needed, e.g. 20 MHz for LTE. For LTE-A an even more concatenation of several bands is considered, which probably requires the operation in even higher frequency bands. All these constraints are finally limiting the achievable range of the cell, thus increasing the number of cells needed.
A cost efficient solution for improving the performance of LTE and LTE-A telecommunication networks can be the utilization of relay nodes (RN), which allows installations without having terrestrial broadband access or the need to install a micro wave link. However the use of a given spectrum in a given cell for multiple uses such as (a) connecting user equipments (UE) via an enhanced NodeB (eNB), (b) connecting UEs via a RN and (c) connecting a RN to the eNB, opens a field for new load balancing solutions.
Therefore, load balancing is an advanced measure in an established mobile telecommunication network in order to use in a beneficial way the in-homogeneities with respect to the data traffic within the telecommunication network. Specifically, load balancing is a measure to offload traffic from on cell to another cell or multiple cells, under the pre-requisite that the other cell(s) have sufficient traffic handling capabilities left.
Load balancing can be done by manipulating the Handover (HO) and cell selection parameters for a user equipment (UE). However, this is often not very reliable because the reception of radio signals can be perceived quite differently and may lead to suboptimal HO decisions. For instance idle mode UEs will still camp on their original cell until physical parameters and broadcast parameters are changed in such a way, that a number of UEs decide to camp on other cells. Further, an alignment between idle mode and active mode parameter settings is useful in order to avoid that for UEs changing from idle to active state a HO would be carried out immediately after the state change.
A more reliable method to steer the load balancing is to force handovers to other cells by signaling commands, which enforce a HO although none of the thresholds usually triggering a HO would be crossed. The advantage is that the allocation of the UE to other cells can be ensured, the disadvantage is that precautions have to be taken to avoid that individual UE executing handovers back to the originating cell prematurely. However, the aspects of data load distribution in a radio resource caused by self backhaul cannot be ignored in current load balancing procedures. The relay node would be considered as defining an independent cell, whereas any offload to this cell would increase the backhaul load and thus would cause an unchanged overload situation in the radio resource load of the cell, which comprises a relationship with the relay node.
There may be a need for providing a method for effectively changing the data load distribution within a relay enhanced telecommunication network.